A Method of Simultaneous Determination of Astronomical Latitude, Azimuth and Time from Observations of an Unknown Star

This paper endeavours to evolve a method of simultaneous determination of astronomical latitude, azimuth and time from the observed vertical angles and differences of recorded times and horizontal angles of an unknown star about an hour before and after the time of elongation, either east or west. The special feature of the method is that it does not require actual identification of the star of observation. The determinations being of an order better than third order precision, the method may have ample applications in both topographic and hydrographic surveys including navigation

A Graphical Method of Adjusting a Doubly-Braced Quadrilateral of Measured Lengths when their Weights are also taken into Consideration

An attempt has been made to develop a graphical method of precisely adjusting a doubly-braced quadrilateral of measured lengths by fitting the least squares method to different systems of weighting, without recourse to elaborate computations and trigonometrical tables. The suggested method is more simple and less time-consuming than the usual methods

Astrofix by Altitudes of Two Pairs of Stars — One Near Meridian and Another Near Elongation

With a view to improving upon the existing methods of simultaneous determination of latitude and longitude by equal or arbitrary altitudes and of separate determination of latitude by meridian and circum-meridian altitudes of stars, an attempt has been made in this paper to introduce an alternative method of astrofix from observations of only two pairs of stars — one for latitude near meridian transit and the other for longitude (time) near elongation. This method is claimed to be not only simpler and quicker but also more completely free from the usual errors of both vertical collimation and constant of atmospheric refraction. Apart from its general use in geodetic surveys, the method is also of considerable importance in topographic and hydrographic surveys, and in navigation

Azimuth from Observations of Close Circumpolar Stars

In this paper suggestions have been made to modify considerably the existing time-azimuth and altitude-azimuth formulae to obtain more easily and quickly the first-order and second-order azimuths from observations of close circumpolar stars using lesser numbers of figures in both logarithmic and machine computations with the help of some small correction tables only. A simple chart has also been designed in order to read immediately from the chart third-order or less precise azimuths from observations of the above stars without recourse to elaborate computations. First-order azimuths are used in geodetic surveys while second-order and third-order azimuths have ample applications in topographic and hydrographic surveys including navigation